A great many types of liquid dispenser pumps are known in the prior art. Some of these pump arrangements have been designed specifically for use in dispensing liquid soaps and the like. The dispenser pumps may be actuated directly by hand or through a suitable intermediate mechanism. Soap dispensers employed for institutional use have commonly been wall mounted and incorporate cabinets with refillable reservoirs used to supply the pump mechanism which routinely is part of the cabinet.
A relatively more recent development has been to employ wall mounted cabinets which are essentially holders for a disposable bottle or other container having all or part of a pump mechanism fixedly attached thereto. When empty, the container and that portion of the pump affixed thereto are discarded.
Throw-away, non-refillable container and pump combinations are particularly appropriate and useful to prevent contamination of the soap or other liquid to be dispensed and to insure that the liquid being dispensed is of a particular type and character. For example, hospitals and other health care facilities often wish to make certain that a disinfectant-type of soap is always being dispensed from a dispenser. If the dispenser were refillable this would not necessarily be the case. Also, of course, there is always the possibility of contamination if refilling is permitted. Hospitals and other health care facilities are in fact increasingly requiring the use of bags or other collapsible containers having affixed thereto a disposable pump mechanism which does not allow the intrusion of ambient air during the dispensing process.
It will be appreciated that a disposable pump must be inexpensive as well as suitable for its intended purpose. Materials costs are of course a factor as are simplicity of pump design and ease of assembly. Many of the existing disposable pump constructions are characterized by their relatively high cost and complexity and it is an object of the present invention to provide a pump for liquid soap and the like which is simple, reliable in operation, and inexpensive in construction.